KANJANA SRIPRASERT1, SUCHADA VEARASILP2, SA-NGUANSAK THANAPORNPOONPONG2, NATTASAK KRITTIGAMAS2, SANGTIWA SURIYONG21Chiang Mai University, Postharvest Technology Institute, Thailand2Chiang Mai University, Department of Agronomy, Thailand
Types and quantities of seed-borne fungi on rice seed cv. Khao Dawk Mali 105 were assessed by using blotter method. Fusarium sp. and Curvularia sp. were found as the main fungi 20.67% and 2.25%, respectively. Various concentrations and volumes of non"=ionic polyacrylamide (PAM) were applied to control seed"=borne fungi on rice seed. It was found that the speed of germination was increased to 15.10seedlingday-1 after treated with PAM at 1% w/v and with the volume of 2 ml/25 g seed. The increasing of PAM concentration reduced the speed of germination of coating rice seed. However, coating seed with all PAM concentrations showed no significantly effect on the germination percentage.

Combination of PAM (1% w/v, 2 ml/ 25 g seed) and clove and star anise essential oils at different concentrations: 0.01, 0.03 and 0.05% were applied to rice seed. Coating seeds then subjected to their quality testing and their seed health evaluating. Treated seed with PAM and various essential oils showed the promising results in inhibiting seed borne fungi. The higher concentration of the coating substances, the better the efficacy Aspergillus sp. and Nigrospora sp. were completely 100% under control. Nevertheless, compare to chemical treatment under captan application; captan showed the best in controlling, followed by clove essential oil 0.05% and star anise essential oil 0.05%. Seed qualities; speed of germination, germination percentages were not affected by all treatments.